Belt Length Calculator
Calculate Belt Length
L = 2C + π(D+d)/2 + (D-d)²/(4C)
Estimate Center Distance from Belt Length
Approximate center distance from known belt length and pulley sizes
Formula
L = 2C + π(D+d)/2 + (D-d)²/(4C)
Frequently Asked Questions
How do I calculate belt length for two pulleys?
Use the formula: L = 2C + π(D+d)/2 + (D-d)²/(4C), where C is the center distance between pulleys, D is the large pulley diameter, and d is the small pulley diameter. All measurements must be in the same units.
What is the wrap angle?
The wrap angle is the arc of contact between the belt and pulley. The small pulley always has a smaller wrap angle. A wrap angle below 120° can reduce power transmission efficiency and increase belt wear.
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